Valve spring depressing tool



Dec. 28, 1965 w. R. HEWETT VALVE SPRING DEPRESSING TOOL 5 Sheets-Sheet 1 Filed June 21, 1962 INVENTOR. Wm. m2 R. #EWi-"TT BY 3% qiM ATTORNEYS Dec. 28, 1965 w. R. HEWETT VALVE SPRING DEPRESSING TOOL 3 Sheets-Sheet 2 Filed June 21, 1962 147' T ORA/E X5 Dec. 28, 1965 w. R. HEWETT VALVE SPRING DEPRESSING TOOL 3 Sheets-Sheet 3 Filed June 21, 1962 l tlgffk Q. 6% i JTTOR/VEKS United States Patent 3,225,427 VALVE SPRING DEPRESSING TOOL Walter R. Hewett, Jacksonville, Fla., assignor to Valerie J. Carter, Jacksonville, Fla. Filed June 21, 1962, Ser. No. 205,823 6 Claims. (Cl. 29-217) This application is a continuation-in-part of now abandoned application bearing Serial No. 144,078, entitled Valve Spring Depressing Tool, and filed October 10, 1961.

This invention relates to a tool for depressing the valve springs of internal combustion engines of the valve-inhead type so as to facilitate the removal of the valve locks or keepers from the valve assemblies thereof and enable the replacement of certain parts of the assemblies. More particularly, the invention pertains to a valve spring depressing tool that is operable without the necessity for removing the engine head, the tool being one which is mountable on the face of the head.

Tools for depressing valve springs so as to enable the removal of the valve locks, or valve keepers as they are sometimes called, and thus permit replacement of such parts of the valve assemblies as the oil seals, spring retainers, springs and locks themselves, are known. Tools which are currently employed for depressing the valve springs of modern engines of the valve-in-head type require removal of the head from the engine in order to mount the tool in operative position. In most cases, the tool has an arm which engages the valve head side of the engine head and another which engages and depresses the spring assembly on the other side. This, of course, necessitates complete removal of the head from the engine in order to mount the tool in a position for it to be operated so as to replace the component parts of the valve assembly on the valve spring side of the head. On the other hand, such parts as the locks, spring retainers, springs, and oil seals can otherwise be exposed for working thereon by simply removing the rocker-arm cover from the engine and the rocker-arm assembly itself. Consequently, the method currently employed is not only time consuming to the mechanic, but expensive to the engine owner. For example, removal of the engine head requires removal of the intake and exhaust manifolds and parts associated therewith, as well as the rocker-arm covers and rocker-arm assemblies.

Tools have been proposed in the past to eliminate the need for removing the engine heads, use being made of the threaded holes which are employed for mounting the rocker-arm supports as a means for mounting the tool on the exposed face of the engine head. One of the disadvantages associated with previously proposed tools, however, is the fact that the screw means provided for attaching the tool to the face of the heads bends or breaks off under the pressures exerted on the tool when depressing the valve springs or else the head itself is cracked, thus rendering such tools useless for their intended purpose.

Still another disadvantage associated with such tools, stems from the use of spring depressing components in the tool which are designed to, at all times, apply forces to the valve spring assemblies which are in parallel with the valve stems so as not to apply lateral components of force to the valves and thereby break the stems or the valve stem guides associated with the springs. Such components make the tools bulky to store in tool boxes and to ship, and render the tools expensive to manufacture as well as cumbersome to employ.

In accord with the embodiments of the invention disclosed herein, the breakage of the head attaching screw components of the tool and of the head itself is avoided Patented Dec. 28, 1965 by providing a component in the tool which engages the face of the head rearwardly of the head attaching element so that the latter is interposed between the former and the point of applied forces to the tool when the tool is engaging a spring assembly. In this way the effectiveness of the head attachment breaking moment applied to the tool when the tool is being used is minimized and the forces applied to the head attachment means are primarily in parallel with the means. Furthermore, it has been observed that the use of complicated structural elements in the tool so as to apply forces to the spring assemblies which are always in parallel to the valve stems are unnecessary and that depression of the springs of the valve spring assemblies can be accomplished without applying excessive lateral forces to the valve stems and valve guides by using an assembly engaging element for depressing the springs which moves relative to a pivot and thereby applies a depressing force to the valve assembly in a direction which is determined by the position of the spring assembly contacting elements relative to the pivot at any one stage in the process of its use.

A general object of the invention is to provide a valve spring depressing tool that is mountable on the face of a valve-in-head engine and which avoids the necessity for removing the head from the engine in order to remove the valve locks or keepers from the valve retaining assembly.

Another object of the invention is to provide a valve spring depressing tool which can be attached to the head of a valve-in-head engine by head attaching elements which engage the head and thereafter be employed for its intended purpose Without cracking the head of the engine and without bending or otherwise destroying the head attaching element.

Still another object of the invention is to provide a tool for depressing valve springs that avoids the use of complicated structural components which are designed for the application of spring depressing forces to the valve assembly that are always in parallel to the valve stems and which is, furthermore, simple and compact in its structural features, valve spring depressing action and inexpensive to manufacture.

Another object of the invention is to provide a valve spring depressing tool which employs a pivoted valve spring assembly engaging element, and accordingly, in use applies a force to the assembly that is determined by the position of the pivot relative to the assembly engaging element thereof but which is, nevertheless, so constructed as to avoid the application of excessive components of force which are lateral to the valve spring assemblies when in use.

Still another object is to provide a valve spring depressing tool which can be used to accomplish its intended purposes Without removing the head from the engine and which is furthermore adapted for use with engines produced by different manufacturers.

Other and further objects of the invention will be apparent from the following disclosure and description contained hereinafter taken in conjunction with the accompanying drawings wherein:

FIGURE 1 is a perspective view of a tool embodying certain concepts of the invention.

FIGURE 2 is a fragmentary top view of the tool shown in FIGURE 1, the tool being shown therein as attached to the face of an engine head. FIGURE 2 illustrates the attached position of the tool in relationship to the intake and exhaust valve assembly of the cylinder shown in FIGURE 5 and also depicts, when taken in conjunction with FIGURES 3 and 4, the position of the tool at an early stagein the depression of a valve spring.

FIGURE 3 is a cross-sectional view, generally along 3 the line 33 of FIGURE 2, illustrating the means employed for mounting the tool on the head of the engine.

FIGURE 4 is an enlarged fragmentary side view of the valve spring retaining mechanism of FIGURE 3 and 1n conjunction therewith illustrates the position of the pivoted spring retainer contacting fingers of the tool when first contacting the retainer mechanism, and further illustrates the play between the spring retainer and keeper retaining sleeve of the retainer mechanism.

FIGURE 5 is a side view of the tool, with certain parts broken away, as it appears in use for depressing the spring of valve spring assembly, and illustrates the positions of the various components of the valve assembly and of the tool at an advanced stage in the process of depressing the spring, certain parts of the engine and valve spring assembly being in section and other parts being illustrated in broken lines.

FIGURE 6 is a side elevational view of still another embodiment of the invention, this embodiment being provided with certain adjustable features that enable the adaptation of the tool to use with valve spring assemblies of different design such as those for engines produced by different manufacturers.

FIGURE 7 is a front elevational view of the tool shown in FIGURE 6.

FIGURE 8 is a plan view of the tool shown in FIG- URE 6, certain components being in section.

FIGURE 9 is a sectional view of the tool shown in FIGURES 6, 7 and 8 taken generally along the lines 99 of FIGURE 8.

With particular reference to the embodiment shown in FIGURE 1, the tool is generally indicated at 1 and includes a rigid, elongated, flat, base plate member 2, which is adapted to rest on a face portion of the engine head, and a rigid generally flat forked arm 3, which is disposed above and pivotally attached to the plate 2. Arm 3 is adapted to engage the spring retaining mechanism when the tool is in use, and terminates forwardly of plate memher 2 in forwardly extending, laterally spaced fingers 4 and 5 for purposes of such engagement. Tool 1 is also provided with a head attachment element in the form of a bolt 6 and an arm depressing mechanism 7, which is pivotally attached to the plate for drawing the arm 3 downwardly toward the plate 2 when the tool is operatively manipulated to depress a valve spring.

The arm drawing mechanism 7, of the tool, has an elongated externally threaded screw member 8, which is pivotally attached at its lower end 10, to the fore portion 9, of plate 2, as by means of pivot pin 11. It also includes a handle carrying, internally threaded, hollow cylindrical member 12, which is adapted to threadedly engage the upper end of screw member 8 and to cooperate therewith when operatively manipulated in pivotally depressing arm 3 toward plate 2 when the tool is in use. The handle 13, has a yoke-type end 14, which enables the handle to freely pivot from one side of member 12 over the end 15 thereof to the other side and is pivotally attached to the upper end 15 by means of suitable pivot pins, such as the pin 17 which engages yoke-arm 18. A corresponding pin is provided for arm 19 of the yoke so as to avoid interruption of the hollow portion 20, and thus permit free passage of screw member 8 therethrough when desired or necessary. The lower portion of the threaded member 12 is provided with an outwardly radially projecting flange or collar 21, which is adapted to engage the upper surface 22 of the arm 3 and to bear thereagainst when the tool is being used.

The fingers 4 and 5 of the arm 3 are provided with depending flanges 24 and 25 along the outer edges 26 and '27 thereof, so as to prevent lateral movement of the spring retainer relative to the tool when the tool is being employed. Fingers 4 and 5 are so spaced as to enable the valve stem as well as the locks, and sleeve of the spring retainer assembly hereinafter described to pass upwardly therebetween when the spring mechanism is depressed for purposes of removing the locks. The arm 3 is also provided with a longitudinally extending slot 28 upwardly through which the screw member 8 extends when the tool is in use. Slot 28 opens forwardly into the space 29 between the fingers 4 and 5 so that the drawing mechanism 7 may be easily pivoted forwardly between the fork-forming fingers and thereby provide greater compactness for shipping and storage purposes.

At the rear 30 of plate 2 there is provided an integrally formed up-standing extension of the plate to which the arm 3 is pivotally connected as by means of pin 32. Extension 31 is of suflicient height to provide a means to pivotally connect the flat-arm member 3 in a position such that the fork-forming elements 3 and 4 of the arm are substantially in parallel with the plate and the upper surface of the spring retainer mechanism when the fingers are in spring depressing engagement therewith.

Slightly rearwardly of the pivotal attachment of the drawing mechanism 7 to the plate, a longitudinally extending slot 33 is provided as a passageway through which the stem end 34 of a head securing bolt 6 extends for securing the plate 3 to the head of the engine. The slot 33 enables preliminary alignment of the tool relative to the spring mechanism prior to finally fastening the plate 2 securely to the engine head as would be accomplished by drawing the head 35 of the bolt 6 into bearing contact with the upper face of the plate.

With particular reference to FIGURES 2 and 3, the tool is therein shown attached to the head 42 of the engine and in position to depress spring 50 by engagement with the spring retaining mechanism 37 of the intake valve assembly 38 associated the cylinder 39, the latter being shown in FIGURE 5. The cylinder also has the usual exhaust valve assembly 40 as well as the intake assembly, and FIGURE 2 also shows the intake valve assembly for the next cylinder. Also shown in FIGURE 2 is the head of the bolt 41 utilized in securing the engine head 42 to the engine block 43 (see FIGURE 5) and rises 44 and 45 of the head upon which the rocker-arm supports (not shown) are normally mounted by suitable threaded fastening elements (not shown) which cooperatively engage within such threaded holes in the rises as are shown at 46, 47, 48 and 49. The rises of the head casting, as is well known, are integral components thereof and are so positioned as to be slightly offset from and between the respective valve assemblies associated with each cylinder in most cases.

The spring retainer mechanism 37 (FIGURES 2, 3 and 4) is of the conventional type and includes a pair of semi-cylindrical lock elements 51 and 52 which are adapted to snugly fit around the respective side portions 53 and 54 of the upper end 55 of the valve stem 60 and which are downwardly and inwardly tapered along their outer side surfaces 56 and 57 so as to be held in position by wedging engagement within an outer sleeve 61. Each lock is provided with an inwardly projecting lip portion 58, which is adapted to engage within the circumferential recess portion 59 at the end 55 of the valve assembly 60 in the usual manner, and the locks are retained in the valve stem engaging position shown in FIGURE 4 by means of a cylindrical open-ended sleeve 61 of the mechanism 37 which surrounds the locks and which is provided with a downwardly and inwardly tapered cylindrical wall 62 that bearingly engages the wall surfaces 56 and 57 of the locks 51 and 52 and thereby wedgingly maintains the locks in stem retaining position by reasons of the upward thrust which is applied to the sleeve 61 by the valve spring 50 through the intervening spring retainer 63. The spring retainer 63 of the mechanism 37 is also generally cylindrical in shape and in addition to the normal radially outwardly projecting and spring over-lapping flange portion 68, is provided with a downwardly and inwardly tapered cylindrical wall 64 which loosely surrounds and is spaced slightly outwardly of the sleeve 61 so as to enable a small amount of play and lateral movement of the retainer 63, relative to the sleeve, sleeve 61 being provided with a small, radially extending, outer flange 65 at the top to maintain the sleeve 61 in a generally central position within the retainer 63. The retainer 63 is provided with an inwardly, radially projecting bottom flange portion 66 which functions as a seat that bears upwardly against the lower end 67 of the sleeve 61 under the influence of the spring 50 and thereby imparts the necessary lock retaining thrust to the sleeve.

As previously stated or inferred, the upstanding extension 31 of the plate 2 provides a means to which the flat arm 3 is connected to the plate in a manner such that when in use, the fingers 4 and 5 are substantially in a plane normal to the axis of the valve stem 60 or, in other words, parallel to the upper surface 69 of the spring retainer 63. This enables the fingers, when the tool is operatively manipulated, to apply a spring depressing force to the retaining mechanism 37 which is substantially in parallel to the valve stem 60, and thereby avoid the transmission of valve guide or valve stem breaking forces of a lateral nature to the valve stem. Actually, the pivotal connection 32 and the fingers of the arm 3 are so positioned in the embodiment as to provide a disposition of the fingers 4 and 5 relative to the surface 69 of the spring retaining flange 68 such that upon use of the tool, first engagement with the flange 68 is effected with the fingers disposed in a plane which is at a slightly elevated angle to the surface 69, and thereafter upon depressing the spring 50 to the point of enabling the removal of the locks 51 and 52 the fingers are disposed at a slightly downward angle relative to the plane normal to the valve stem 60. The sleeve bearing flange 66 of the retainer is suitably spaced from the surface of the valve stem 60 as to enable some lateral movement of the retainer relative to the sleeve at the bottom of the retainer.

The loose nature of the fit between the walls of the spring retainer 63 and the sleeve 61 is advantageous in that it facilitates the use of spring depressing forces which are slightly off parallel with the stem without causing the retainer to bind against the stem and thus disrupt the stem surface or cause breaking of the stem and its guide. Thus, as the arm 3 of the tool first engages the flange 68 of the spring retainer, the spring retainer on the tool side is depressed and gives downwardly a little against the spring, as shown in FIGURE 4, without causing the flange 66 to bind against the valve stem 60 as the fingers come into full contact with the upper surface of the spring retainer flange 68. Thereafter, as the arm is forced downwardly, the forces are uniformly applied to the spring and the retainer and spring are depressed until the locks can be removed from the mechanism. Accordingly, the lateral component of force which is applied to the retainer mechanism 7 by virtue of the pivoted arrangement is but slight and is absorbed primarily by the spring 50 itself rather than being transmitted to the valve stem 60 and from there to the valve guide.

FIGURE 5 further illustrates the action of the tool in depressing the spring mechanism and the method of using the same. With particular reference thereto and to the engine parts and assembly shown therein, the internal combustion engine is generally depicted at 71 and includes the block 43 having a cylinder chamber 39 in which the usual piston 72 is located. The intake manifold is designated at 73 and the associated carbureting parts of the engine are generally indicated at 74.

The head 42 of the engine is of the usual cast type and includes an intake port 75 which communicates with the intake manifold 73 and cylinder chamber 39 of the engine, and a valve guide 76 which is cast integral therewith. The guide 76 is open-ended and opens into the intake port 75 and through the upper face 77 of the head 42 so that the valve stem 60 of valve 78 extends upwardly from the port through the valve guide 76 to a point exterior to the head 42, the head 79 of the valve being so disposed in the port 75 as to operatively close and open the port when actuated by the rocker-arms (not shown). Passing through the side of the head 42 and opening into the cylinder chamber 39 is a threaded passageway in which is normally disposed a sparkplug which is usually removed during use of the tool but which is generally depicted at 80.

Spring 50 of the intake valve assembly 38 shown in FIGURE 5 is disposed surroundingly above the upper portion 81 of the valve guide 76 and is based against the face of the head rise 82 which is an integrally cast portion of the guide 76. The spring 50, of course, is normally maintained in a compressed state by contacting the spring retainer 63 of the spring retaining mechanism 37 and is constantly urging the valve head 79 into close relationship when the valve assembly is fully assembled.

In the illustration of FIGURE 5, valve depressing tool 1 is shown depressing the spring 50 by contact with the spring retainer mechanism 37, the valve '78 in the illustration of FIGURE 5 having thereby been permitted to fall from the closed port position illustrate-d by dotted lines 83 to contacting engagement with the end of piston 79. Piston 79 is always maintained at its top center firing stroke when the tool described herein is being used to depress a valve spring associated therewith so as to prevent the valve, such as valve 78, from falling into the piston chamber 39 and thereby necessitating the removal of the head 42 to reposition the valve in the guide 76. The positioning of the piston 79 to the top of chamber 39 is readily accomplished by removing the sparkplugs from the head and simply adjusting the piston to the desired position by rotating fan 89.

In utilizing the tool 1 to disassemble a spring retaining mechanism, such as mechanism 37, the tool is first mounted on the upper face 77 of the head 42 adjacent to the mechanism. In the case of the illustrated embodiment, the tool 1 is mounted on the face of rise portion 44 of engine head 42. This is accomplished by placing the plate 2 upon the rise and inserting the bolt 6 through the slot 28 provided in plate 2 such as illustrated in FIGURE 3, and thereafter tightening the bolt 6 securely in threaded hole 47 which is utilized for mounting the rocker-arm support. Prior to securing the tool rigidly to the base of the head, the fingers 4 and 5 are suitably aligned to contact the upper surface of the flange of spring retainer 63 and thereafter the internally threaded member 13 of the drawing mechanism 7 of the tool 1 is manually screwed down on externally threaded member 8 through the use of handle 13, thus forcing the retainer contacting fork elements 4 and 5 downwardly onto flange 68 of the spring retainer such as illustrated in FIGURES 3 and 4. Further compression of the spring 56 enables the valve stem to fall down into contact with the piston 72 (see FIGURE 5). Whereafter, as the element 12 is further screwed down on threaded member 8, the spring 50 is further compressed and the locks 51 and 52 retained at the upper end of stem 60, pass upwardly between the forked elements 4 and 5 thus permitting their removal from the retainer mechanism. Thereafter, disassemblyment of the spring retainer mechanism 37 is easily accomplished by unscrewing the member 12 from the member 8 and freeing the arm 3 from the retainer mechanism, thus enabling removal of the sleeve retainer and the other parts of the valve assembly which secure above the head thereby. As shown in FIGURE 5, a removable oil seal 84 is surroundingly disposed about the upper end of valve guide 76 and the stern of the valve 78 and may be easily replaced through use of the tool.

It is deemed apparent that in reassembling the spring retaining mechanism, for example, after having replaced the oil seal 84, that the process is the reverse of the disassembly of the mechanism. Thus, after placement of seal 84 about the stem of valve 78 and in contact with the upper end of valve guide 76, the spring 50 is positioned on rise 82, whereafter the spring retainer 63 is i positioned at the upper end of the spring and the sleeve 61 may, if desired, be inserted therein. Thereafter the forks 3 and 4 of the arm are aligned to cooperatively engage the flange 68 of the retainer 63 and the element 12 is screwed down into bearing relationship against the upper surface of the arm 3 and the arm is caused to pivot on pivot 32 downwardly toward plate 2 thereby depressing the spring 50 to the point where locks 51 and 52 may be inserted in the spring retaining mechanism and in contact with the recessed portion of the valve stem. The locks are thereafter manually held in place as the arm 3 is caused to pivot upwardly of the plate 2 by unscrewing element 12 until the locks are secured by engagement with the sleeve 61 of retainer mechanism 37. Thereafter, the tool can be released from contact with the spring retaining mechanism, 37 and when desired, loosened from and rotated on its mounting in rise 44 to a position to engage the valve assembly 40 as shown in FIGURE 4. This process can be repeated by shifting the tool from one rise to the next in accord with the particular valve assembly which needs part replacement as is obvious.

As best shown in FIGURE 5, the portion 85 of the plate 2 of the tool which extends rearwardly of the bolt 6 contacts the rise surface portion 86 of the upper face 77 of the head. This portion 85 of the plate, as well as the portion 87 thereof which contacts the edge surface 88 of the head provide the tool with a head bearing member which counteracts the moment of force applied to the bolt 6 when the fingers of the tool are in spring depressing engagement, and which tends to bend the bolt and thereby cause breakage thereof and cracking of the engine head. Thus, the portion of the plate 2 which is rearwardly of the bolt 6 prevents the stem of the bolt 6 from snapping off in the rise of the head, and causes most of the forces imparted to the bolt by reason of the action of the spring assembly on the tool to be carried by the stem of the bolt in a direction which is generally parallel to the axis of the stem.

The embodiment shown in FIGURES 6, 7, 8 and 9 is generally designated at 100 and is provided with an arm depressing mechanism 104 that has components which are common to the means utilized for securing the tool to the head of the engine. Tool 100 also has a mechanism 101 for adjusting the spacings between the valve spring assembly engaging fingers 102 and 103 of the tool so as to enable its use with various spring assemblies that have diflierent sized components. To this same end, tool 104) is also provided with means that permit relocation of the pivot axis of the arm relative to the base plate 105 of the tool so that the arm can be adjusted to pivot about an axis which is suitable for the particular valve spring assembly being depressed so as to avoid imparting undue lateral force components to the valve stem when the tool is used.

Base plate 105 of tool 100 is formed by an elongated U-shaped member 106 which also forms a slot 107 between the opposite legs 108 and 109 thereof. Slot 107 opens rearwardly at the rear portion 110 of the plate. The rear portion 110 of the plate is fixed to an upright channel member 111 which is welded to the upper surface of the plate with the flanges 112 and 113 of the channel facing rearwardly of the tool. Each of the flanges is provided with a plurality of rearwardly opening notches 114 that are vertically spaced from each other and horizontally aligned with corresponding notches in the other flange so that the pivot member 115 for arm 116 of the tool can be selectively placed in the slots formed by the aligned notches and retained therein by a plate-like retainer indicated at 117.

Plate 117 is adapted to cover the rearward opening between the flanges 112 and 113 of channel member 111 and also the notches 114 in the respective flanges, as seen in FIGURES 8 and 9. The upper end of the plate 117 is releasably secured to member 111 by a Wing nut 119 carrying headed threaded element 118 which passes through a hole 120 at the upper end 121 of the plate 117 and through an aligned hole 122 at the upper end of the rigid channel 111, as seen in FIGURE 9. The lower end 123 of the plate 117 is connected to an L-shaped element 124 which is integrally formed with the plate and which extends into the rearward opening in slot 107 and laps the bottom end of the channel 111 with one leg 125 of the element 124 projecting upwardly at the front face of the channel 111 thereby forming a lip which retain the bottom portion of the plate in place, as seen in FIGURES 6 and 9.

The arm 116 of tool 100 is composed of separate elongated members 127 and 128 which are spaced apart at the rear end of the tool by and on opposite sides of channel 111. Members 127 and 128 are interconnected at the opposite sides of the channel by a headed bolt 115 which also connects the members to channel 111. Bolt 115 passes, through the rear end portions of the members 127 and 128 and lengthwise through the slot formed by one set of the aligned notches 114, as seen in FIGURE 9. Bolt 115 establishes an axis for pivotal movement of the arm 116 and member 127 and 128 are retained thereon by nut 130 which is threaded on the end of the bolt.

Members 127 and 128 are generally disposed above plate 105 and project forwardly of the front portion 133 of the base plate to terminate in space fingers 102 and 103 respectively at the front ends 131 and 132 of the member. The front end portions of members 127 and 128 are bent in opposite lateral directions as seen in FIGURE 8 and have downwardly projecting flanges 134- and 135 which lap the edges of the spring retainer of the valve assembly when the tool is in use. These front end portions 131 and 132 are also provided with inwardly extending top flanges 136 and 137, as seen in FIGURES 7 and 8, and which are designed to engage against the upper surface of the spring retainer when the tool is in use. These flange portions 136 and 137 are integral portions of the members 127 and 128, as seen in FIGURES 6 and 7.

Elongated arm forming members 127 and 128 are maintained in the same plane of operation by means of threaded element 138 which extends snugly through but remains rotatable in a suitable hole 139 (FIGURE 8) in member 128 to threadedly engage member 127. Element 138 forms a component of the finger spacing mechani sm 101 and carries a coiled compression spring 140 WhICh surrounds the element between the members 127 and 128 and which also form a component of the mechanism 101. Compression spring 140 operates against lnwardly projecting protuberance portions of the members 127 and 128 and constantly urges the members 127 and 128 and their fingers 102 and 103 apart.

Members 127 and 128, like the other components of the tool 100, are made of a suitable metal and by reasons of their minor horizontal cross sectional dimensions are capable of bending in the horizontal direction when element 138 is screwed in against the urgings of spring 140. The members 127 and 128 are sufficiently resilient, however, to return to their normal position, shown in FIGURE 8, when element 138 is again adjusted to permit the members to assume the normal position. Com pressrve spring 140 tends to keep the member 127 and 128 apart and more particularly tends to keep member 128 agalnst the head of screw element 138 so as to avoid any play in the spacing between the fingers 102 and 100 as when nut 130 becomes slightly loosened on element 115. By reasons of the major vertical cross-sectronal dimension of members 127 and 128, these members are more or less inflexible to bending in these directions, and accordingly are capable of withstanding the necessary forces encountered in depressing a valve spring.

The means employed for attaching the tool 100 on the face of the engine head is designated in the drawings at 141, and includes an elongated bolt 142 which is threaded and adapted to screw into the head of the engine, as for example, into the threaded hole 47 shown in FIGURE 3. Bolt 142 is common to the arm depressing mechanism 104 and to the head attaching mechanism 141 and, in the illustrated embodiment is threaded substantially throughout its entire length. When the tool is in use it extends vertically through the slot 107 at the front end 133 of the base plate 105 and upwardly through the space between arm forming members 127 and 128. Mechanism 141 also includes a pair of nuts 143 and 144 which are threaded on the lower end of the bolt 142 and located between the base plate 105 and arm 116 when the tool is in use. When the tool 100 is being placed in position for use, bolt 142 is screwed into the head of the engine, and nut 143 is then screwed down on the bolt 142 to securely clamp the plate 105 to the face of the engine head. After this nut 144 is screwed down into engagement with nut 143. Nut 144 serves to lock nut 142 in place. Nut 143, as seen in FIGURE 7 is of sufficient size to engage the upper surface of the plate forming legs 108 and 109 so as to enable its use in clamping the plate to the face of the engine head.

Arm depressing mechanism 104 includes, in addition to bolt 142, nut 145 and a small plate-like element 146 which is provided with a hole 127 through which the bolt 142 extends and which is adapted to rest on the arm forming members 127 and 128.

Hole 147, through which the stem of the bolt 142 passes, is located between the opposite sides of the plate and is of sufficient size to permit the stem to loosely extend therethrough. Plate element 146 has downwardly extending flanges, shown at 148 and 149, at its opposite sides, and which are primarily designed to prevent the plate from rotating, on the bolt stem and out of contact with the members 127 and 128 when the arm is being depressed. The flanges 148 and 149 engage the sides of the respective arm forming members when plate 146 is caused to rotate and act as stops.

Nut 145 is of sufiicient size to lap the edges of the plate 146 above hole 147, and when screwed down on the plate 146 forces the arm 116 by reasons of the forces transmitted to members 127 and 128 through plate 146 to pivot downwardly against the upward urgings, such as indicated by arrow 150, of the valve springs.

When tool 100 is to be employed for depressing a valve spring, the tool 100 is first secured to the face of the engine head adjacent the valve assembly to be worked on. This is accomplished by first screwing bolt 142 into the appropriate hole in the engine head adjacent the valve assembly to be worked on. Thereafter, and prior to fixing the plate 105 firmly to the engine head, the body of the tool is adjusted relative to the bolt so that the fingers 102 and 103 are generally in a working position to engage the spring retainer of the valve spring assembly. Thereafter nuts 143 and 144 are tightened down to fix the plate 105 firmly on the face of the engine head.

Once the tool is fixed to the engine head, pivot element 115 is positioned in the proper slot formed by the aligned notches 114 in channel member 111. This can be done by removing plate 117 so that element 115 can be relocated to the selected slot without disengaging the connection between the arms by the pivot element 115 and nut 130, after which the plate is again placed on the back of the channel 111 and secured thereto by nut 119 and element 118. On the other hand, the relocation of pivot pin 115 can also be accomplished by removing nut 130 from the end of the pin 115 and by withdrawing the pin from the slot and from the holes in the rear ends of the members 127 and 128, and by thereafter replacing the pin in the holes and in the newly selected slot in the 10 channel 111 and securing the members 127 and 128 thereon by replacement of nut 130.

It will be obvious from the description contained herein with respect to the embodiment shown in FIGURES 15 that the selected slot for pin should be such as to enable the fingers 102 and 103 to pivot with respect to the axis in a manner such as to depress the valve spring without unduly applying lateral force components to the valve stem.

Following the above procedure, the finger spacing mechanism 101 may also be adjusted by manipulating screw element 138 so that the flanges 134 and 135 just fit over the opposite side edges of the radially extending flange of the spring retainer. Thereupon nut may be screwed down on bolt 142 to force the fingers to pivot downwardly toward plate 105 and about the axis established by pin 115 in the selected slot so as to depress the spring of the valve assembly to the point where the locks may be removed in the manner and for the purposes previously shown.

By use of a base plate, such as plate 105, which is adapted to engage the face of the head rearwardly of the head attaching elements, force components which tend to crack the head of the engine when the valve spring is being depressed are minimized and/or avoided as before mentioned. Tool 100 has the advantage of the adjustable features heretofore mentioned which enable its use with various valve assemblies having different size components.

It is deemed evident that the components of the tool are made from materials which will suitably withstand the stresses to which the respective components are subjected, metal such as steel obviously being preferred.

While only certain preferred embodiments of this invention have been shown and described by way of illustration, many modifications will occur to those skilled in the art and it is, therefore, desired that it be understood that it is intended in the appended claims to cover all such modifications as fall within the true spirit and scope of this invention.

What is claimed as new and what it is desired to secure by Letters Patent of the United States is:

1. A tool for use in depressing the spring of a valve spring assembly of an internal combustion v-alve-in-head engine without detaching the head thereof comprising a rigid plate, engine head attaching means for rigidly securing said plate on the upper face of an engine head, an arm pivotally connected to the plate rearwardly of the head attaching means, said arm having means extending forwardly of the head attaching means for engaging the spring retainer of a valve spring assembly, and means connected to the plate and cooperatively engageable with the arm for drawing said arm pivotally downwardly toward said plate, said plate including means disposed rearwardly of the head attaching means for bearingly engaging the face of the engine head upon securing said plate thereon.

2. A tool for use in depressing the spring of an internal combustion valve-in-head engine valve spring assembly without detaching the head of the engine, comprising a rigid plate member having a front portion and a rear portion, threaded engine head attaching means extending through the front portion of said plate for mounting said plate on the face of the engine head, a forked member disposed above said plate and pivotally connected to the rear portion thereof, said forked member having a pair of fingers extending forwardly of the front portion of said plate for engaging the spring retainer of said assembly, and means pivotally connected to said plate and cooperating with said forked member to draw said forked member downwardly toward said plate, said plate including means disposed rearwardly of the engine head attachment means for hearing against the face of the engine head when said plate is mountedon the face of the engine head.

3. A tool for use in depressing the valve spring of a valve spring assembly of an internal combustion valve-inhead engine without detaching the head thereof comprising an elongated, fiat plate having an upstanding rear extension, a forked arm disposed above said plate and pivotally connected to the upstanding extension, said arm having parallel laterally spaced fingers extending forwardly of said plate for engaging a spring retainer of the valve spring assembly, a bolt having a threaded stem adapted to pass through said plate forwardly of said extension for engaging the engine head within a threaded rocker-arm support mounting hole to secure said plate on the face of said head, a threaded member pivotally connected to said plate forwardly of said extension, said threaded member being adapted to pivot forwardly from between said fingers, and a manually manipulatable member threadedly engaging the aforementioned threaded member for forcing said arm downwardly toward said plate.

4. A tool for depressing a valve spring of an internal combustion valve-in-head engine to remove the locks from the spring retaining mechanism associated therewith comprising a base member, spaced fingers for engaging the upper surface of a valve spring retainer, means above and carrying said fingers forwardly of said base member and in substantially parallel alignment with the engaged surface of the valve spring retainer, said means being pivotally attached to said base member, and means cooperating with said base member for rigidly connecting said base member to the face of the engine head adjacent to the valve spring, and manually manipulatable means for forcing said fingers to pivot into contact with the valve spring retainer, said base member including surface means disposed rearwardly of said means cooperating with said base member adapted to engage the face of the engine head when said base member is connected to the face of the engine head.

5. A tool for use in depressing the spring of a valve spring assembly of an internal combustion valve-in-head engine without detaching the head thereof comprising a base member having a front portion and a rear portion, elongated means disposed above said base member including spaced fingers extending to in front of said front portion, rigid means fixed to said rear portion and extending thereabove, means connecting said elongated means to said rigid means and establishing an axis for pivotal movement of said elongated means, and means for releasably securing said base member on the face of the engine head adjacent to the valve assembly and for forcing said fingers against the valve assembly to depress the valve spring thereof, said rear portion including surface means disposed rearwardly of the means for releasably securing said base member on the face of the engine adapted to bear against the face of the engine head when said base member is secured thereon.

6. A tool for use in depressing the spring of a valve spring assembly of an internal combustion valve-in-head engine without detaching the head thereof comprising an elongated upright member having rearwardly opening and vertically spaced horizontally extending notches, an elongated base member having a front portion and a rear portion, said base member being rigidly secured to said upright member at said rear portion and extending forwardly of said upright member, a pair of spaced members extending forwardly of said upright member, said spaced members having spaced fingers disposed in front of said front portion of said base member, pivot means extending through a selected one of said notches and connected to said spaced members for establishing a pivot axis for pivotal movement thereof, retainer means releasably secured to said upright member for retaining said pivot means in the selected one of said notches, means for releasably securing said retainer means to said upright means, and means for releasably securing said base member on the face of the engine head adjacent to the valve assembly and for forcing said finger downwardly against the valve assembly including an elongated threaded element extending through said base member and adapted to threadedly engage the head of the engine forwardly of said rear portion, manually manipulatable means cooperating with said threaded element for keeping said base member against the face of the engine head, and manipulatable means cooperating with said threaded element for pivotally moving said spaced members downwardly against the valve assembly, said rear portion of said base member including surface means adapted to engage the face of the head when said base member is secured thereon.

References Cited by the Examiner UNITED STATES PATENTS 1,051,633 1/1913 Price 29-218 1,499,843 7/1924 Peterson 29-218 1,974,363 9/1934 Miller 29-215 2,049,484 8/1936 Worrall 29-215 2,940,166 6/1960 Moore 29-219 WILLIAM FELDMAN, Primary Examiner. NEDWIN BERGER, MILTON S. MEHR, Examiners. 

1. A TOOL FOR USE IN DEPRESSING THE SPRING OF A VALVE SPRING ASSEMBLY OF AN INTERNAL COMBUSTION VALVE-IN-HEAD ENGINE WITHOUT DETACHING THE HEAD THEREOF COMPRISING A RIGID PLATE, ENGINE HEAD ATTACHING MEANS FOR RIGIDLY SECURING SAID PLATE ON THE UPPER FACE OF AN ENGINE HEAD, AN ARM PIVOTALLY CONNECTED TO THE PLATE REARWARDLY OF THE HEAD ATTACHING MEANS, SAID ARM HAVING MEANS EXTENDING FORWARDLY OF THE HEAD ATTACHING MEANS FOR ENGAGING THE SPRING RETAINER OF A VALVE SPRING ASSEMBLY, AND MEANS CONNECTED TO THE PLATE AND COOPERATIVELY ENGAGEABLE WITH THE ARM FOR DRAWING SAID ARM PIVOTALLY DOWNWARDLY TOWARD SAID PLATE, SAID PLATE INCLUDING MEANS DISPOSED 